hey asm, thanks for the words of advice... my reasons for a 4x6' router are many. First, I want to be able to do more than just mill guitar bodies. I know several carpenters in the area that would be more than happy to throw some work my way, if I could produce detailed wood pieces. I'd like to get into machining columns, mantle pieces, custom moldings, and signs of all types.
Once the machine is built and properly set up, routing guitar bodies or necks will be trivial.
At any point in time, ebay has tons of servo/stepper motors, linear bearings, ball screws, etc at decent prices. You just have to check every day, and invest a bit in luck for winning the auction. Remember we are talking about milling wood here, at a low feed rate. Im going to use a Dremel as the router for development...
Why not try and build a cnc? I have adequate skills with electronics, due to having a BS degree in electrical engineering. Heck, my day job is software/hardware development. If I really start digging into the software/motor control aspects of the project (which I'm just starting to now), I could probably write a crude program for motor control. Plus, We aren't talking tolerances to a 1000's of an inch.
I would argue that it's entirely possible to do. My only problem now is finding the time to do it, with work/school and everything else, but once im done gathering parts i'll start to piece something together and start looking for control boards. It's going to be a learning process, but think of the application once its done? for a couple grand (at most) I'll have the ability to make a ton of cool stuff.